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极低浓度甲烷气体爆炸后固体产物研究

煤炭技术 2025年第1期44卷 194-197页

作者：宋来臣紫金矿业集团股份有限公司福建龙岩364000

在煤炭开采过程中,有大量的低浓度难利用的甲烷气体直接排入大气或经燃烧后排入大气。为探索低浓度甲烷的可利用性,通过向极低浓度甲烷中掺混其他可燃气体降低爆炸极限,并对爆炸后固体产物研究为极低浓度甲烷的利用提供了新思路,针对爆... 详细信息

在煤炭开采过程中,有大量的低浓度难利用的甲烷气体直接排入大气或经燃烧后排入大气。为探索低浓度甲烷的可利用性,通过向极低浓度甲烷中掺混其他可燃气体降低爆炸极限,并对爆炸后固体产物研究为极低浓度甲烷的利用提供了新思路,针对爆照固体产物的分子结构和孔隙结构2个方面对爆炸固体生成物进行红外光谱测试、电镜扫描、透射电镜扫描,结果表明:爆炸的固体生成物中含有大量的芳香烃结构和-OH官能团,其次是-C≡C-H、C-H、C-O结构,芳香烃结构在炭黑形成过程中起重要作用。

关键词：极低浓度甲烷掺混爆炸固体产物芳香烃结构

Multi-infill strategy for kriging models used in variable fidelity optimization

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Chinese Journal of Aeronautics 2018年第3期31卷 448-456页

作者： Chao song Xudong YAnG Wenping song national Key Laboratory of Science and Technology on Aerodynamic Design and Research Northwestern Polytechnical University

In this paper, a computationally efficient optimization method for aerodynamic design has been developed. The low-fidelity model and the multi-infill strategy are utilized in this ***-fidelity data is employed to provide a good global trend for model prediction, and multiple sample points chosen by different infill criteria in each updating cycle are used to enhance the exploitation and exploration ability of the optimization approach. Take the advantages of lowfidelity model and the multi-infill strategy, and no initial sample for the high-fidelity model is needed. This approach is applied to an airfoil design case and a high-dimensional wing design *** saves a large number of high-fidelity function evaluations for initial model construction. What＇s more, faster reduction of an aerodynamic function is achieved, when compared to ordinary kriging using the multi-infill strategy and variable-fidelity model using single infill criterion. The results indicate that the developed approach has a promising application to efficient aerodynamic design when high-fidelity analyses are involved.

关键词： Aerodynamics Infill criteria Kriging models Multi-infill Optimization

第一性原理对M@B_(12)n_(12)(M=Sc-Zn)团簇结构和性质的研究

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原子与分子物理学报 2025年第4期42卷 93-99页

作者：张颂程露吴学科凯里学院理学院凯里556011

利用基于密度泛函理论的第一性原理对M@B_(12)n_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)n_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明... 详细信息

利用基于密度泛函理论的第一性原理对M@B_(12)n_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)n_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明显增大.过渡金属原子与B_(12)n_(12)结合的过程中,除Cu和B原子外,剩余金属与n原子的Mulliken电荷出现负值.另外,金属原子的加入,不仅增加电偶极矩和极化率的值,还促使其红外吸收光谱发生红移.

关键词：团簇结构性质第一性原理

Robust Iterated Sigma Point FastSLAM Algorithm for Mobile Robot Simultaneous Localization and Mapping

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 693-700页

作者： song Yu song Yongduan LI Qingling Center for Intelligent System and Renewable Energy Beijing Jiaotong University Beijing 100044 China State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150080 China Institute of Automation Chinese Academy of Sciences Beijing 100190 China

Simultaneous localization and mapping （SLAM） is a key technology for mobile robots operating under unknown environment. While FastSLAM algorithm is a popular solution to the SLAM problem, it suffers from two major drawbacks： one is particle set degeneracy due to lack of observation information in proposal distribution design of the particle filter; the other is errors accumulation caused by linearization of the nonlinear robot motion model and the nonlinear environment observation model. For the purpose of overcoming the above problems, a new iterated sigma point FastSLAM （ISP-FastSLAM） algorithm is proposed. The main contribution of the algorithm lies in the utilization of iterated sigma point Kalman filter （ISPKF）, which minimizes statistical linearization error through Gaussian-newton iteration, to design an optimal proposal distribution of the particle filter and to estimate the environment landmarks. On the basis of Rao-Blackwellized particle filter, the proposed ISP-FastSLAM algorithm is comprised by two main parts： in the first part, an iterated sigma point particle filter （ISPPF） to localize the robot is proposed, in which the proposal distribution is accurately estimated by the ISPKF; in the second part, a set of ISPKFs is used to estimate the environment landmarks. The simulation test of the proposed ISP-FastSLAM algorithm compared with FastSLAM2.0 algorithm and Unscented FastSLAM algorithm is carried out, and the performances of the three algorithms are compared. The simulation and comparing results show that the proposed ISP-FastSLAM outperforms other two algorithms both in accuracy and in robustness. The proposed algorithm provides reference for the optimization research of FastSLAM algorithm.

关键词： mobile robot simultaneous localization and mapping (SLAM) particle filter Kalman filter unscented transformation

Elevated CO_2 changes the moderate shade tolerance of yellow birch seedlings

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Journal of Environmental Sciences 2007年第4期19卷 502-507页

作者： CHEnG song Department of Biology Concordia University 7141 Sherbrooke Street West Montreal Quebec H4B 1R6 Canada Wuhan Botanical Garden Chinese Academy of Sciences Wuhan 430074 China.

To demonstrate the existence of light thresholds in plant growth and to examine the effects of elevated CO2 on the shade tolerance of a tree species, an experiment consisting of a completely randomized design for a total of 96 yellow birch （Betula alleghaniensis Britton） seedlings was conducted with 3 light levels （2.9%, 7.7%, 26.1% of full sunlight） × 2 CO2 levels （350 and 700±10 ppm） with 4 replications in a phytotron. The study proved that thresholds exist and they vary in different plant organs. In ambient CO2, the thresholds were 13.3%, 18.7%, 15.0%, 15.2%, and 15.6% of full sunlight for stem, leaf, root, total plant biomass, and the averaged value, respectively. In 700 ppm CO2, the corresponding thresholds were 16.7%, 21.3%, 18.1%, 21.7% and 19.5% for stem, leaf, root, total plant biomass, and the averaged value, respectively. The lowest threshold in the stem is an indicator of the minimal light intensity for regular growth for seedlings of this species. Below this threshold, light-stressful growth occurs. The result of a paired t-test indicated that the thresholds in elevated CO2 were significantly higher than in ambient CO2. This suggests that yellow birch will lose its moderate shade tolerance, evolutionally becoming a shade-intolerant species, and that it may become more difficult to naturally regenerate in the future.

关键词： elevated CO2 light threshold phytotron plant biomass yellow birch

Morphological structure and peripheral innervation of the lateral line system in the Siberian sturgeon (Acipenser baerii)

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Integrative Zoology 2012年第1期7卷 83-93页

作者： Wei song Jiakun song Institute for Marine Biosystem and neuroscience Shanghai Ocean UniversityShanghaiChina

Light and scanning electron microscopy(SEM)were used to study the epidermal lateral line system of the Si-berian sturgeon(Acipenser baerii Brandt,1869).This system consists of mechanoreceptive neuromasts,ampul-lae and the electroreceptive *** neuromasts are located in 5 pairs of cephalic and 1 pair of trunk canals and superficially in the middle and posterior pit lines that lie dorsomedially along the top of the skull immedi-ately adjacent to the otic ampullae *** canal neuromasts and pit organ superficial neuromasts have oppo-site polarized hair cells that are parallel along the axis of the canal and pit line,***,they dif-fer in both size and shape and in the density and length of the hair *** ampullae are confined on the head,adjacent to the neuromast *** morphological structure of the ampullae in the Siberian sturgeon is similar to the ampullae in elasmobranchs and other primitive ***,it has a relatively large mucus-filled ampulla,and a shorter and narrower canal leading to a small opening to the outer epidermal *** also present new information concerning the peripheral innervation of lateral line receptors in *** re-ceptors of the lateral line system are innervated by 2 pairs of cranial nerves:anterior and posterior lateral line *** peripheral processes of the anterior lateral line nerve form superficial ophthalmic,buccal,otic and anteroventral *** peripheral processes of the posterior lateral line nerve form middle,supratemporal and lateral rami.

关键词： canal neuromasts electroreceptors lateral line nerves mechanoreceptors pit organ superficial neuromasts sturgeon

nUMERICAL SIMULATIOn STUDY On DEFORMATIOn UnIFORMITY OF EQUAL CROSS SECTIOn LATERAL EXTRUSIOn

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Acta Metallurgica Sinica(English Letters) 2004年第1期17卷 61-63页

作者： Z.L.Chang J.L.song n.H.Hao Department of Materials Engineering Taiyuan Heavy Machinery Institute Taiyuan 030024 ChinaDepartment of Materials Engineering Taiyuan Heavy Machinery Institute Taiyuan 030024 ChinaDepartment of Materials Engineering Taiyuan Heavy Machinery Institute Taiyuan 030024 China

Equal cross section lateral extrusion (ECSLE) is an effective method realizing pure shear deformation. The influence of friction factor on the deformation uniformity of ECSLE was investigated with rigid plastic finite element method. The result shows that the non-uniform deformation in extrusion is caused mainly by the friction between workpiece and die. The higher the friction factor is, the more uneven plastic deformation resulted in extruded workpiece. The relation curve of deformation uniformity vs. friction factor was drawn based on the analysis result. The curve can be used as a basis of ECSLE process design.

关键词： equal cross section lateral extrusion strain finite element method

The sensory world of fish and fisheries: Impact of human activities–An international conference to evaluate the effects of environmental changes on the sensory world of fish/aquatic animals and fisheries

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Integrative Zoology 2015年第1期10卷 1-3页

作者： Jiakun song Shaun P.COLLIn Arthur n.POPPER Institute for Marine Biosystem and neuroscience College of Life Sciencesand International Center for Marine Studies Shanghai Ocean UniversityShanghaiChina School of Animal Biology and the Oceans Institute The University of Western Australia CrawleyWAAustralia Department of Biology University of Maryland College ParkMDUSA

This special issue of Integrative Zoology(the official journal of the International Society of Zoological Sciences and the Institute of Zoology,Chinese Academy of Sciences)is dedicated to the sensory world of fish and fisheries and the impacts of human *** papers in this issue are the outcome of an international conference that was held at the Institute for Marine Biosystem and neurosciences,College of Fisheries and Life Science,Shanghai Ocean University,Shanghai,China from 29 October to 1 november *** conference was generously sponsored by The Shanghai Ocean University,The University of Maryland and The University of Western Australia.

关键词： fish Impact journal

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基坑施工影响下地铁隧道现状分析及安全评价

工程建设 2025年第1期57卷 73-79页

作者：齐伟宋冉中铁投资集团有限公司天津300251 中国铁路设计集团有限公司天津300251

为解决邻近地铁隧道的建(构)筑物施工对既有隧道现状的影响和隧道安全评价问题,以某地铁区间隧道在周边配套基坑工程施工期间发生的破坏现状为例,综合隧道现状检测结果、隧道变形形态分析和安全余度计算结果,评价分析区间隧道结构的现... 详细信息

为解决邻近地铁隧道的建(构)筑物施工对既有隧道现状的影响和隧道安全评价问题,以某地铁区间隧道在周边配套基坑工程施工期间发生的破坏现状为例,综合隧道现状检测结果、隧道变形形态分析和安全余度计算结果,评价分析区间隧道结构的现状安全性。结果表明:隧道变形基本稳定,管片受力未超过极限弯矩,隧道结构安全;隧道结构裂缝及渗漏水情况可控,耐久性能够满足短期使用要求;隧道变形未超过建筑限界,满足功能要求;为确保邻近基坑的施工安全及地铁区间隧道的运营安全,建议加强隧道内结构变形监测,并对隧道内渗漏水、裂缝、裂损等病害进行修复。本文结果可为近接地铁隧道施工情况下的隧道结构安全状态分析和评价提供一点参考。

关键词：基坑施工地铁隧道隧道现状安全评价

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